This paper considers some known abstract domains for affine-relation
analysis (ARA), along with several variants, and studies how they
relate to each other. We show that the abstract domains of
Mueller-Olm/Seidl (MOS) and King/Sondergaard (KS) are, in general,
incomparable, but give sound interconversion methods. We also show
that the methods of King and Sondergaard can be applied without
bit-blasting -- while still using a bit-precise concrete semantics.